Saw



gc. s. BUSQUE I 820,434

SAW

Filed Oct. 24, 1930 INVENTQR Uliarieys fizmeb'n 52254906 I ATTORNEY- Patented Aug. 25, 1931 UNITED 1 STATES ATENT] FFI E j CHARLES s. Buso E, 0F sm. ernnoiv DE BEAUCE, ,QUEBEQQ'CANLADA QsAw ' Application filed octoterzgieem sard ne/191,047-

This invention relates to improvements in circular saw teethand-more particularly to saw teeth offthe insertible ty e, such as used in saw mills for cutting lum er,-and it con-' sists in the novel features, which are hereinafter more-fully described. Y

One of the objects of my invention is to provide teeth for saws of a design adapted for sawing across the grain of the wood, as may be required in logging and pulp. cutting operations, lumber manufacturing plants, butti 'lng machines, etc. as well as for sawing lengthwise the grain or with the grain, as 1n most lumber sawingr Another objectofmy invention is'to design a saw tooth, which will have the advantage of making cleaner cuts in both lumber sawing and general cross-cutting.

Another object of my invention, is to save labor and time consumed in refiling saw teeth byproviding a sawtoothof a design, which wood.'-

other objectof my invention is to will be less frequently 1 worn down by use.

A further object ofmy invention is to save power by providing a saw tooth, which ,re-

quires less effort to propel it through the A still provide insertible saw teeth. which, when new,

i may be readily introduced into old saws to replace one or more worn teeth therein, with:

' out thereby interfering with the proper functioning of the saw.

' Another objectof invention is to pre- I I'attain theseobjects the :saw tooth,

vent springing or deflectionjof the saw. teeth, or parts thereof asv when encountering tough 'partsin the wood, such as frozen knots at a diagonaliwith thegrain. r g

. A furtherobject of the invention is to prevent wabbling of the saw.

A still further object of my: invention is to leave the? wood adjacent the cut therein substantially' smooth andeven without any fibers being torn. therefrom I in cross-cutting saws of 'the' present design.-

Other objects and advantages willherein after appear.

one form of whichis illustrated in the accompanying drawings or. by any mechanical as in equivalent or obvious modification of the 7 same.

' In the drawings,

1 Fig. 1 is an end View of my improved saw tooth, lookingfrom left 'toright in Fig- 2. Fig. 2 is aside view of my improved saw action of the ordinary chisel pointed or edged saw tooth in cross-cutting, the saw tooth rip ping away the fibres of thewood.

. Fig. 6 is a sketch, illustrating the perfected action ofmyiinprov ed sawtoothin severing the fibres of the wood by the incision of grooves thereinto by means of flanking blades or flangesonthe saw tooth and the scooping of the detachedfand isolated fiber segments ibetween the said grooves bythe' chisel point or edge of thetooth.

Like numerals refer to out the 'several'views. g

In the drawings '11 and'12 designate a pair like parts through- M V f of parallel flanking knife edged incision blades or flanges'on a saw tooth, which form therebetwe'en a channelshaped groove 15 on the outenend of 1,3 and4.

- The said the tooth, as 'shown'in Figs'.-.

blades or flanges" ll' and' 12'have thereon" two relatively :long parallel edges,

and they are shown as longer in the direction. r" of rotation off the saw than thechisel point. p or edge 13 of the saw; tooth,which edge is shown as positioned forwardly of said blades 1.1 and 12.

' d The blades 11 and 12 are vroundedon their forward ends as at 16,; Fig. 2, and are shown ,to the'heel'14' of the tooth.

as extending in a; substantially straight line 7 The direction of rotation of the saw' is ini I dicatedb'y the arrow 17 in Fig. '2 and the dot anddash arcuate lines 18'and 19 represent respectively the, paths of the leading point 13a of the chisel point or edge 13 of thesaw tooth andthe i railing points 20 of said blades 11 and 12; duringthe rotationaof the saw. I

Ordinary chiselpointed vorchisel edged teeth have a tendency to draw or feed excessively, when employed to saw across the grain, to the point of making such teeth useless for this purpose; this is due to the fact that when sawing by means of these chisel pointed or edged teeth the fibers 0f the wood are being ripped from the body of the wood when the latter is not being out onboth sides of the line of sawing in a direction towards the center of the saw and in advance of or past the circular line 19 which is described by the chisel points or edges 13a, as is done by means of my improved saw tooth.

In Fig. 5 an illustration is given of the manner in which standard saw teeth are ripping away the fibers of the wood in cross-- cutting. This action is due to the fact that the fibers 21 are subjected to a bending strain and a shearing strain across the grain of the wood by the action of the saw tooth. point or edge; and, the resistance of the fibers 21 to bending and shear across the grain being greater than their resistance to shear lengthwise the grain, the fibers 21 are being ripped from the body 22 of the wood to an extent that leaves the surface of the wood multilated adjacent the cut; and the wood is being drawn by this ripping action towards the saw, thereby producing excessive feed, as hereinbefore mentioned.

In Fig. 6 an illustration is given of the more perfect action of my improved saw tooth whereby lateral grooves 23 and 2 1 are formed in the body 22 of the wood across the fibers 21 thereof by means of said flanking incision blades 11 and 12, whereof the rounded forward ends 16 are provided there? on to prevent ripping thereby of said fibers 211 V Said blades 11 and 12 actby pressure only, thereby severing the fibers 21 of the wood on both sides of and in advance of the action of the chisel point or edge 1.3 of the tooth, of which the action is restricted to scooping out the fragments of the fibers 21, which are left between the lateral grooves formcd'by the action of said blades 11 and 12; th saction together with that of the chisel point or edge 13'leaves a shallow tongue 25 between the rernn ants of said grooves 23 and 24, after the major part of the material between said grooves has been removed by said pointer edge 13.

Said blades 11 and 12 are set to extend further outwardly from the saw tooth than the point 13a of said chisel edge 13, whereby wood. 22 is engaged by said blades 11 and 12 in' advance of said point 131;, thereby forming said flanking grooves '23 and 24in advance of the scooping action by said chisel point or edge 13, and thereby preventing ripping of the fibers 21 by the'latter.

The above described arcuate lines 18 and 19 designate respectively the furthest extent of the action respectively of said blades '11 and and the fragments of the fibers 21 between said grooves are being continually removed from the tongue 25 between said grooves until the body 22 of wood is completely sawed across, the last vestige of the tongue 25 falling away from the parted fragments of the wood 22 without having its fiber fragments scooped up by the chisel point or edge 13.

The above described design and action of a my improved sawtooth allows a relatively very acute angle to be provided between the outer end of a saw tooth and the said lines 18 and 19, thereby causing the wear on said chisel point 13 and blades 11 and 12 to be exerted in a direction, which is almost tangential, or parallel to said lines 18 and 19, instead of being radial with relation to the saw.

This feature allows the introduction of one or a few new saw teeth among a set of already used saw teeth without requiring more than a few expert strokes of a file to make them coincide with the relative positions of the old teeth, to obtain perfect functioning of the saw.

The provision of the flanking blades 11 and 12, which are preferably integral with the tooth, prevents misalignment and springing ofthe'saw teeth between said chisel or edge 13 and said blades 11 and 12 when encounterinn suliistances, such as frozen knots at a diagonal with the grain'of the Wood, when more resistance is encountered by the sides of the teeth whichfirst engage these obstacles; the presence of said flanking blades on the saw tooth integrally therewith and with said chisel point 13 resists deflection of the tooth towards the side thereof, which encounters:

the lesser resistance thereto.

The copious length of the parallel flanking blades 11 and 12 causes the outer edges of the latter tobe pressed with greater force into initial cuts traced by the rounded forward ends 16 thereof, and gradually to deepen the said cuts, thereby holding the chisel point oredge 13 of the tooth intermediate of the said pair of cuts formed by said blades 11 and 12 and in perfect alignment therewith, thereby preventing wabbling of the saw and enhancing the proper functioning of the same.

The shavings, which are scooped up by the chisel points or edges 13 between said grooves and and inwardly of said tongue 25, as shown Fig. 6, are rolled into the gullet of the saw, until they are ejected from the cut in the wood, leaving no particles to be wedged between the faces of thecut in ducing the resistance to the rotation of the saw and thereby reducing the. powerconsumed by the saw.

The said incision blades 11 and 12 are posi:

tioned substantially parallel to each other as shown in Fig. 4; the inner sides of said blades are shown in Figs. 1 and 3 as bevelled the wood and the blade of the saw, thereby reto a substantially sharp angle, to promote incision or cutting by said blades, and the. outer sides of said blades are almost but not quite parallel to the sides of the saw tooth, being slightly bevelled inwardly with rela-- tion to the saw, to reduce friction'of said outer sides with the wood during the operation of the saw.

Many changes may of my improved circular saw teeth without be made in the details departing from the main scope of my inven- I tion, and parts of my. invention may be used without other parts, 1

I do not, therefore, restrict myself to the details as shown in the drawings, but I intend to include also allmechanical equivalents and obvious modifications of the. same within the scope of my'invention.

I claim as my invention and desire to secure by Letters Patent:

'1. In a circular saw tooth a chisel edge on the outer end of the. tooth and a pair of thereby.

incision blades, positioned to flank the outer end of the saw tooth, forming therebetween a channel shaped groove on said end, the outer edges of said blades extending further outwardly than the forward point of said I chisel edge, said blades being shaped to bite into the wood without ripping it, thereby to form grooves in the wood on the flanks of the part thereof, which isto be removed by said I chisel edge and in advance of the action of I said chisel edge, thereby preventing ripping 'of the wood by said chiseledge. I I

g 1, said incision "blades being positioned substantially par'-, allel to each other and to said saw tooth,

2. The elements of claim thereby avoiding ripping ofthe wood' thereby.

3. The elements'of claim 1, said incision blades being integral with said saw tooth and said chisel edge thereon, thereby enhancing I the strength and rigidity of said tooth,

4.. The'elements of claim 1, said incision blades having the forward ends thereof rounded, to prevent ripping of the wood 5. The elements of claim 1, said incision blades having thereon at the outer" edges thereof knife edges, whereby effectively to ripping the same.

. The elements of claiml, the outer end of. said saw tooth being inclined rearwardly and cut grooves in the woodbypressure, without V 

